unable to kill -9 for zombie process

[Ismail Azad]

Hi,

Every process or service has a "graceful" way of exitting and talking in terms of process, a zombie in any terminology would always mean "dead" but not as harmful as a "ghost" or a "living dead" in the sense that it's just " a memory release" that happened in a weird fashion leaving an entry in the "process table", a table that was rigid on 8.x but is now called as a "process list" as it is no more rigid.

The "graceful reboot", does this in the clean fashion and gets rid of this "defunct" stuff. Or as mentioned kill the master zombie to get rid of the dead.

Regards
Ismail Azad

[Yarok]

Well. it seems that I found the reason for the zombie effect.
I reconstructed it and the same senario, including ~100% cpu process occured.

I used a local script that "bring down" the inner software and kills all processes which involved with it.

Then I reconstructed it again, but this time I used the ptree script (for HP UX - shows all process and thier parents). I found the parent zombie process that called then I ps -ef | grep defunct to kill -9 it.
The zombie disappeared but still the cpu process was very busy (~100%).

Shoulnt the zombie killing necessarily low the cpu ?
Any suggestion?

[Patrick Wallek]

>>but still the cpu process was very busy (~100%)

If you invoke 'top' or 'glance' what is the process that is using the most CPU? Is it related to the zombie or is it something completely different.

[Yarok]

I use the 'top' command and the cpu using process rising up to 100% (and more... how can it be?) as per time factor (minutes).

>Is it related to the zombie or is it something completely different.

I run the top parallel to the problematic process (on other HP machine) and most of time I saw the zombies (they are also rises as a factor of time).
When I bring down the process the cpu usage immediately goes back to its normal level and the zombies disapear, except of 1 the alwas exists (I dont know how or who is its parent).

[Dennis Handly]

>(and more... how can it be?)

Using threads.

>When I bring down the process the CPU usage immediately goes back to its normal level and the zombies disappear,

Well, you killed the zombie master.

>except of 1 the always exists (I don't know how or who is its parent).

A child of ia64_corehw?

[Yarok]

Yes, I can see that ia64_corehw is runnig.
what is this process (monitoring the HW)?
Why its child is zombie?

BTW, I noticed that is exists on other HP machine.

[Dennis Handly]

>I can see that ia64_corehw is running.
>what is this process (monitoring the HW)?

This is a known problem in the diagnostic software, fixed on 11.31.

[Yarok]

thank you all for the information.